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aculeus

noun
acu·​le·​us | \ə-ˈkyü-lē-əs\
plural aculei\ ə-​ˈkyü-​lē-​ˌī \

Definition of aculeus 

zoology

: a sharp-pointed process specifically : an insect's ovipositor especially when modified into a sting

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First Known Use of aculeus

1702, in the meaning defined above

History and Etymology for aculeus

borrowed from New Latin, going back to Latin, “stinger, spine (of a fish), sharp point, barb,” from acū-, stem of acus “needle” + -leus, noun suffix (perhaps originally diminutive)

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The first known use of aculeus was in 1702

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